Burkhead was a core special-teams player in Cincinnati but was ultimately buried on the depth chart behind Giovani Bernard and Jeremy Hill. He did not start his first game until his fourth and final season in Cincinnati.

Burkhead took on a more significant role in the final six games of the season after Bernard tore his ACL. He averaged 4.6 yards per carry, the highest among Cincinnati's running backs, carrying the ball 74 times for 344 yards and two touchdowns. He averaged 8.5 yards per reception, catching 17 passes for 145 yards.

Rex Burkhead was buried on the Bengals' depth chart and is headed to New England. Evan Habeeb/USA Today Sports

Burkhead has lined up as a slot receiver and kick returner, and his versatility likely intrigued the Patriots. If the Patriots don't re-sign LeGarrette Blount, Burkhead will compete at running back with Dion Lewis and James White and would probably have more potential to move up than he did with the Bengals.

Burkhead was clearly stuck down the depth chart in Cincinnati. Although he looked the part in 2016, it was probably going to be hard to re-sign him without the potential for a bigger role.

The Bengals also had concerns about Burkhead's durability as a lead running back, a role currently occupied by Hill, who had injury problems of his own last season with a shoulder/chest issue and a knee ailment.

Hill, the Bengals' 2014 second-round pick, is entering the final year of his rookie contract.

Although Bernard and Hill have shared running back duties for several years now, that won't stop the Bengals from exploring their options at the position. The Bengals hold the No. 9 pick in the draft and have shown interest in former LSU running back Leonard Fournette, who is projected to go early in the first round.

The Bengals have also visited twice with former Oklahoma running back Joe Mixon, meeting with him privately before his pro day and also hosting him in Cincinnati for a visit.

Mixon was not invited to the NFL combine because of his off-the-field conduct relating to a 2014 incident in which he struck a female Oklahoma student, breaking several bones in her face.

The Bengals will need to at least bring in another backup now that they are down to Bernard, Hill and practice squad running back Tra Carson on the roster.

Running back Cedric Peerman, who played mostly on special teams, is an unrestricted free agent. His special-teams role was also occupied by Burkhead when Peerman was on IR for half of the 2016 season.